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TaeKwonDood writes "Your granddad's approach to fishing — throw the little 'uns back — may have hurt their evolution, but we can reverse that, says a group of researchers, with a change of policy.
Fish have been 'reprogramming' themselves to be smaller and live longer. Welcome to evolutionary dynamics, Lamarck. But, no, they are serious. And it can be fixed within 12 generations. What do the smart people out there think about this? Are they using the term 'evolution' the wrong way?"

What do the smart people out there think about this? Are they using the term 'evolution' the wrong way?

Of course not! Hollywood would be proud!

Oh, and they can get it down to 6 generations if they reroute the power from the main EPS conduits through the deflector dish in order to create a reversed polarity tachyon field. The tachyons will interact with the quantum state of the fish at a subatomic level, forcing them to grow larger. Sort of like inflating a balloon. With tachyons.

Nope. It seems correct to this biology teacher. This is a clear case of directional selection [wikipedia.org]. Keep eliminating the larger fish and the median size of fish in the population will be smaller. So, by taking the large ones, we are selecting against them and for smaller fish and juveniles. If, over time the frequencies of the alleles for large and small change in the population, then we have, by definition, evolution.

of course there are actual biologists who read slashdot that don't think highly of evolution being thought of in terms of a ladder but rather fitness and genetic change over time in order to maximize the chances that organisms can and do reproduce. the summery did a poor job of phrasing what the researchers actually said on the matter calling it "bad for their evolution" in contrast to being "undesirable [from humanity's perspective] evolution" for which the latter is far more accurate and the former.

of course there are actual biologists who read slashdot that don't think highly of evolution being thought of in terms of a ladder but rather fitness and genetic change over time in order to maximize the chances that organisms can and do reproduce. the summery did a poor job of phrasing what the researchers actually said on the matter calling it "bad for their evolution"

The summary was bad but the actual article does have this quote from Dr Conover "the bigger and older a fish is, the more offspring it prod

I'm just waiting for some self-righteous slashdotter to draw an analogy between the runts of the litter, promotion to management, 12 generations, and their least favorite CEO. If you can breed lapdogs in 12 generations, with nothing but artificial selection, imagine what you can do with specimens who are actively trying to "evolve" themselves.

throw the little 'uns back â" may have hurt their evolution, but we can reverse that

*cringe* evolution is not a step ladder! If the fish are adapting genetically with the result being more offspring than they would otherwise then it is evolution regardless of humanity's shallow view of what it means to "evolve in a positive direction" or that just because those fish didn't evolve the way we would have liked that it somehow means that it "hurt their evolution."

just because those fish didn't evolve the way we would have liked that it somehow means that it "hurt their evolution."

I'd in fact go further and say it has helped their evolution. If they become small enough that us humans cannot be bothered with them then they have managed to eliminate the most dangerous predator on the planet as a concern. Seems like a smart move to me.

More precisely, you can't 'hurt' or 'help' evolution - you can't even really evolve in a 'bad' direction since evolution by definition increases the survivability of the species. An individual mutation could be good or bad, but evolution is the process of selecting the good mutations.

As you say, in this case 'good' means 'humans don't eat me'.

Now, TFA may mention this (but how would I know?), but the clever thing for fishermen to do is to catch the biggest, tastiest fish and then breed them. This leverages evolution by making 'tasty to humans' a survival trait. If you doubt this works, consider sheep, pigs, cows, wheat and rice.

Bananas are a bad example. They might be a lot easier to eat these days, but they can't reproduce on their own anymore. They're also so limited genetically, because they don't reproduce like plantains do, that a banana-specific bacteria or mold or something could totally decimate a very large supply of the fruit.

And this is why agricultural research and seed preservation needs more government funding and not less. Part of both the Bush and Obama administrations' budget cuts have included this (a quick google search will net you several news articles on the subject).

I don't know - once one of the selection pressures is an intelligent force that can predict the eventual path of evolution, I'd say words like, 'hurt' can start to apply.

What if the fish evolving to be smaller to avoid human mouths eventually leaves them set to be eliminated by some other force? In other words, what if we're forcing a short term evolutionary advantage that is long term fatal to the species?

Natural selection works to increase the fitness of the average individual in a population sure, but Evolution also includes cases where the average fitness level can go down. Consider, for instance, the founder effect [wikipedia.org].

What if the fish evolving to be smaller to avoid human mouths eventually leaves them set to be eliminated by some other force?

If that force is worse than humans then evolution would work in the opposite direction because small fish would be being preferentially selected for dinner leaving the big ones to survive. Evolution is a beautiful feedback mechanism.

Exactly! This is like saying that throwing apples on the ground is hurting gravity. I also don't understand why we feel the need to associate words like good or bad with evolution. The only thing that is good or bad is when the effect of evolution affects us in some way. Is entropy acting mean today?

Exactly! This is like saying that throwing apples on the ground is hurting gravity. I also don't understand why we feel the need to associate words like good or bad with evolution. The only thing that is good or bad is when the effect of evolution affects us in some way. Is entropy acting mean today?

It's interesting to see how inconsistent people here do tend to be.

I would hazard a guess that there is a much higher percentage of atheists and agnostics among slashdotters than what is in the general population, so I just don't get the whole ascribing good/evil tags to human impact upon evolution. As I understand it, there is no right or wrong in evolution, only cause and effect.

If one ascribes no special status to humans (e.g. "made in the image of God"), then how can we be anything more than cause

I would hazard a guess that there is a much higher percentage of atheists and agnostics among slashdotters than what is in the general population, so I just don't get the whole ascribing good/evil tags to human impact upon evolution. As I understand it, there is no right or wrong in evolution, only cause and effect.

I have said a number of tymes on/. that I am agnostic, "a" - without and "gnosys" - knowledge and so without knowledge as far as a higher power or being, but I still believe in good and bad. Th

Respectfully, I guess that I never quite understood that. Outside the context of the supernatural, how is behavior either good or bad? Why isn't it just homo sapiens behavior, like it would be in any other species?

That behavior is either good or bad implies that we have a choice in our behavior (i.e. free will). No one has ever made a strong case to me that--outside the existence of a higher being--that we're all not in a completely deterministic universe. If you subscribe to the notion that the exac

Respectfully, I guess that I never quite understood that. Outside the context of the supernatural, how is behavior either good or bad? Why isn't it just homo sapiens behavior, like it would be in any other species?

We all have our own ideas of what's good or bad.

That behavior is either good or bad implies that we have a choice in our behavior (i.e. free will).

To a certain extent we all have free will, though not all of us can control our behavior all the tyme. I used to be easy going and didn't get angry,

More precisely, you can't 'hurt' or 'help' evolution - you can't even really evolve in a 'bad' direction since evolution by definition increases the survivability of the species.

Sure species can evolve in a bad way. Birds [wikipedia.org], especially flight-less birds, in New Zealand evolved to live there. However since westerners brought cats, dogs, and rats many species have gone extinct and others are threatened. Simply when a species becomes specialized

you can't even really evolve in a 'bad' direction since evolution by definition increases the survivability of the species.

Tell that to the dinosaurs who evolved to be nice and big just before the meteor hit. Evolution only acts to increase the immediate survivability of the species it does nothing for longer term, foreseeable events.

Good point but the reason they ended up in this situation is that no one has invented a net that catches small ones and lets the big ones go. We eat all sizes of marine creatures from shrimp and white bait to whales and if they get smaller we will jst use smaller and smaller nets.

There seems to be no limit on our urge to exploit to extinction all life on the planet that we cannot farm. So nice try fish but we're gonna get ya

I'm beginning to wonder if it's worth it to come here if the blurbs misrepresent the articles so badly.

well yeah, the summeries on slashdot can be pretty bad but there's two redeeming features about all of this: the article [when it is relevant] and the discussion about said article and potentially about said summery. And the mod points...

"I'm beginning to wonder if it's worth it to come here if the blurbs misrepresent the articles so badly."

I see you are new here, the zen of slashdot is never read TFS/TFA, if you must you can glance at the headline before going straight to the comments. Personally I don't know of any other site where geeks regularly gather in such numbers and diversity to hurl abuse at each other.

I've always thought of evolution as the furtherance of a species through gradual genetic mutations over time. What is described here I've always thought of more as 'natural selection', whereby a specific trait produces an advantage in nature that leads to a higher rate of survival for those that possess the trait.

The difference being that natural selection is one aspect of how evolution occurs, but it's not required; a specific mutation may not directly provide a benefit in the environment; it may take seve

Maybe the use of the word 'reprogramming' -- that could be taken to to mean they were claiming it was something individual fish were doing, to change within their own lifetimes. Hence, Lamarck. But I could just as well read it as a (maybe slightly weird) way of describing the change in the species' genetic distribution as it responds to selective pressure in what (as you said) sounds like a perfectly classic case of evolution. 'Course, that's just based on the summary; to say for sure, I'd have to RTFA.

"If, over time the frequencies of the alleles for large and small change in the population, then we have, by definition, evolution."

No, we haven't. We just have frequency variation. But we haven't change the gene pool a dime. Without new characteristics we have no evolution, by definition.

I have to agree with GP, we indeed have evolution, by definition. Evolution is not defined by "new characteristics", whatever that is. Could you please provide a reference that defines evolution as "new characteristics"?

Evolution is (as I have learned during my biology studies) defined as a change in allele frequency. If the genetic make-up of the population changes from one generation to another (and frequency variation constitutes such a change), then we have evolution.

Furthermore, you assume that only frequencies change. That need not be the case. A phenotypical change in size (as in this case) might also very well be caused by mutation, what might be a "new characteristic". Superficially you have no way if distinguishing the two processes.

"Evolution is not defined by "new characteristics", whatever that is."

I specifically said "new characteristics" because *that* is what evolution is. There's no need to go into technicalities. If you don't have something "new" (for some operative definition of "new") you simply cannot have evolution. Specifically, without some *genetical* change you can't have *genetical* evolution.

"Could you please provide a reference that defines evolution as "new characteristics"?"

"The counter to his comeback on that is "microwalking". That is, he'll say he believes in micro evolution (variation) but not macro-evolution (dino->bird)."

It's only that this is no "counter". I never stated my position about evolution, I only defined it. Saying "there's no way a dino can become a bird" is a counterargument for "biological evolution is the appearence of new characteristics on an species population" no more than saying "yeah, but they don't exist" against "a unicorn is a kind of a horse

Nope. It seems correct to this biology teacher. This is a clear case of directional selection [wikipedia.org]. Keep eliminating the larger fish and the median size of fish in the population will be smaller. So, by taking the large ones, we are selecting against them and for smaller fish and juveniles. If, over time the frequencies of the alleles for large and small change in the population, then we have, by definition, evolution.

What makes you think this wouldn't be an example of evolution?

My take on it is that this is more of a case of Intelligent Design (or Unintelligent Design...whatever, but design either way). And as we all know, ID != Evolution. In fact, many see them as complete opposites. I guess no one has ever considered that maybe evolution is a product of design. In other words, maybe species were "designed" to "evolve".

Not sure why you took "several things" as refering to adaptation vs evolution. It was specifically1. your attitude, which was pointlessly offensive.2. "didn't have legs, now I do after "evolution" takes place." An individual can't evolve, populations do over time.3. You are splitting hairs. This is not an evolutionary biology board, and "adaptation" and "evolution" are commonly used by people who are not evolutionary biologists to mean the same thing. In fact, they're used interchangeably by biologists,

This is an absolutely spot on comment. If there is a selection pressure for smaller fish, then the process of selection is working. "Natural selection" is somewhat of a misnomer, as sometimes something out of the ordinary (occurs with predictable regularity, or slowly over the course of millennia) happens and pressures the group in a certain direction. In this case, humans are applying a selective pressure to the fish population. Therefore fish that are predisposed, due to their genetics, to a smaller ad

Let's assume that some of the fish are small because they're genetically predisposed to being small, and others are small because they haven't gotten big yet.

Let's also assume that human predation is only eliminating the big fish.

So human predation eliminates 0% of the fish predisposed towards smallness, and X% of the fish predisposed towards largeness. End result is evolutionary pressure toward being smaller. It's not absolute, but it does favor the smaller fish.

What does Lamarck have to do with it? These fish haven't been passing down traits they've developed during their lifetimes - we've been killing all the big fish, so smaller fish are selectively left to breed. That's Darwinian evolution.

In normal situations, I'd imagine that bigger fish tend to reproduce more often. But when some external force (e.g., thousands of fishers in boats with GPS and big nets) changes things, you get a different outcome.

If we preferred to eat fish that were darker in colour, they'd be getting lighter instead.

Either TaeKwonDood misunderstands evolution, or rushed to post his article a little too quickly...

I see your point, but I think I agree with Hognoxious. Why mention Lamarck at all?

I thought the invocation of the L-word was related to the weird question about whether the term 'evolution' was being used in the right way. Which dozens of posters above me have answered already, so I defer to them.

Whenever I go out to the bars, I make it a point to take the smallest woman I can find home with me. It is my hope that within generations, the women remaining in the bars will all be larger and provide... um...::analogy fail::

For years, the elephants in southern India have been hunted for their tusks. Fifteen years ago, you could very well run into a lone tusker in the wild with metre long tusks.

But now of late, there are baby elephants being born who grow up to be fertile males without the large tusks. With tiny foot long points out of their mouths, instead of something resembling the original giants [wikipedia.org] that I used to love.

It's almost as if the poachers are even more of a significant selection force than nature and female preference put together.

Technically they are correct, in practice I have my doubts. It is hard to get all the variables in a breeding programme to act in line. Ask any dog breeder.

I once was asked by someone from J. Witnesses if I could transform a human into a crocodile. Sure I said, just give me some 300 million years and I might succeed. And, give give me another 300 million years and I may even get it back to a human.

TFA describes a closed study of a population of fish. It's not an examination of wild populations of fish or an analysis of trends in wild populations. Extrapolating their observations from the closed population and applying them to the wild populations isn't accurate.

Commercial fishing is performed with nets (or longlines) and does not discriminate based on size. Everything in the net goes into the hold. Any non-target fish are discarded after they are dead. Sport fishing does discriminate based on size, but doesn't have a significant impact on saltwater fish. Also, larger fish are usually the smarter fish that have avoided anglers' lures, etc. which is a phenomena that isn't accounted for in this study.

Commercial fishing is performed with nets (or longlines) and does not discriminate based on size.

I gather there's three ways out of a net: through the netting, that is squeezing through the mesh spacing for small objects or fish, out the front of the net, and through any tears in the netting. All three escape routes favor smaller fish. The real issue is whether this selection bias is significant enough to matter. My take is that it isn't unless the fish was originally near the size of the net spacing (if the fishermen are targeting that fish species, the spacing of the mesh will be well below the size

If you spend four hours casting lures in front of a group of > 2' striped bass that you can clearly see in the water and the only fish that bite are smaller, younger, fish, then you'd be familiar with this phenomena known as 'smarter fish.' You could also call them 'wary' fish.

Really, though, I was criticizing the methodology of the study that removes behavior from the selection process. The study assumes fish cannot control their own removal from the gene pool. The researchers simply pulled out fish ba

I read, about twenty-five years ago, that traditional people in the Andes, when planting potatoes, only planted the biggest and most beautiful ones they had from previous harvest. The religious justification is that the "Pacha Mama", which is "Mother Earth", only deserves the best.

The same selection of the smallest happens in the logging industry when people cut down the bigger trees and think the little ones will grow up to fill in. That's called "high cutting" and it will ruin a forest for generations. As much bad publicity as clear cutting gets it's usually the best way to manage timber cutting.

As much bad publicity as clear cutting gets it's usually the best way to manage timber cutting.

Unless there's a stream or buildings downhill from the clear cut. The roots of those trees help maintain the soil, remove them and the soil can be washed away. In streams silt can build up either damming it or making it shallower than otherwise. It can also bury fish eggs. With all that loose soil mudslides [youtube.com] are more likely. Selective harvesting of trees can reduce this.

This is no more evolution than the development of different breeds of dogs, which are all the same species, was evolution. Take a population and select a specific trait. Breed the population to amplify that trait.

Take a population of dogs. Bread the population to be big, and you end up with a population that is bigger and bigger. Eventually, you end up with great danes, mastifs, etc.

Continue this kind of divergent breeding long enough, with a large enough group of traits and one might be able to force evolutionary change and the creation of different species.

This is an example of change due to environmental pressure. But, the pressure has not been applied long enough to make the change permanent or complete.

The article shows a simplistic understanding of the Theory of Evolution and a simplistic and misinformed interpretation of the data.

Um, no, speciation does not have to occur for something to be considered "evolution", only a change in the inherited traits of a population (due to a selective pressure). You are confusing speciation with evolution in general. Evolution can lead to speciation but that is irrelevant.

whether or not evolution brings it about is a somewhat pointless question if you seek some kind of deeper knowledge into the nature of life.

The people generally expressing surprised concern over the question of whether evolution leads to speciation don't strike me as being terribly interested in any kind of "deeper knowledge", but are rather attempting to muddy the waters in favor of their personal religious beliefs.

Evolution includes natural selection and artificial selection. It includes anything that affects the movement of genes through the gene pool from one generation to the next. It is by no means restricted to genetic changes which make an animal reproductively incompatible with a group of its recent ancestors you choose to call a "species". Such distinctions are largely arbitrary, but even if you choose to be straitjacketed by Linnaeun orthodoxy and pinpoint a precise point when one species becomes another,

For instance, I imagine it would be quite simple to find a pair of dogs (or even a pair of dog breeds) that were entirely genetically compatible, but were, for mechanical reasons, unable to interbreed.

Then, would a female primordial dwarf and a man with an extremely thick penis would be considered separate species because they can not couple for "mechanical" reasons?How about to extremely fat people?

other people are willing to consider any change in a population that increases its fitness in response to a c

demanding that they demonstrate a new species every time they talk about evolution is nonsensical

Except that no one debates that selective breeding is possible. The term evolution only gets controversial when you claim that it is able to explain the origins of the species. The former has been directly demonstrated many many times and within human lifespans. The case for the later isn't so clear and direct.

Equivocating the two concepts muddles communication. If someone says they do or don't believe the theory of evolution, it is unlikely they are talking about variation among dog breeds. Either sci

No one posted a comment about getting fish to have laser beams on their heads? Sharks are preferred, but sharks are fish. The little one with little lasers only annoy. We want really big ones with huge lasers to take out our targets!

As someone who does go fishing, I am sort of concerned with this. Commercial fishing has always had a different set of rules then recreational fishing. For example: flounder (or summer flounder or fluke) in my state the size limit is 18 inches with a bag limit of 4 in 2008 (I ha

Now I need to read about how that Japanese guy is making out with the farming of blue fin tuna. If we can farm and release into the wild game fish people want, that would be great and help with the fish stocks. We can just farm these fish then send them to market, but there are those who still want to catch them.

There are problems with farmed fish. One is that farmed fish require vast amounts of feed stock [fishinghurts.com]. To produce 1 pound of fish for the table 5 pounds of fish are required. That feed stock has to be

Just because humans are influencing the system, why is this artificial? We've exerted selection pressure on fish, and they have adapted to fit the pressure. How's this different from any other predator influencing a population?

I agree, it's not artificial. Evolution is, in part, about adaption due to changes.

On another note, though, I don't think they are not growing as big, I think that they are not getting a chance to grow as big. There was a show on National Geographic called Hooked: Monster Fish (http://shopngvideos.com/products/hooked_monster_fish). There are fish growing to be large, we just eat them. Could we just be overfishing the larger ones?